I Just Heard A Weird Set Of Tones Play Through My Speakers

I was resting in my bed watching youtube when i heard what sounded to be a set of notes from a gameboy game play through my heaphones that were plugged in. they were facing the table too, so it must have been pretty loud for me to be able to hear them. i checked my open programs and nothing seemed to be able to do that i had heard so it's really confusing me.
it was a set of 5 notes, then another 5 but up a few notes, and then finished off with 9, another few notes higher.
not sure what's running on my computer to do that but i am currently running a windows security scan to make sure everything is hunky dory. Possible malware or unwanted program?? not sure.

 

Youtube videos often include screen recordings from the uploaders computer or the audio/video they are creating captures any notification they get while recording and that becomes part of the video.

 

do you know what video it was.